If you're totally unable to learn to mount the rifle in such a away as to be able to find the target in the scope, this option might be of value. Back in the old days when an 8X scope had a field of view about like looking down a water pipe, there might have been a real need for such a setup as the one shown. With the variables and much wider fields of view available now, I just can't see the need(for hunting).
I've shot several deer using fixed power scopes at very short range as they jumped from their bed or from cover. At no time did I feel the process would have been made easier by adding a second sighting system that required me to decide which sight I would use in the split second opportunity to shoot and then twist my rifle awkwardly on it's side to access the secondary system.